The segment mode is a very powerful extension to the RS485 analyzer to find faulty activities or data on a bus, even if a lot of (or only two) bus devices share the same line so that the faulty activity can not be directly assigned to a certain sender.
Usually there is a rough or specific idea about which device does not work correctly. If this device or group of devices can be isolated (not electrically) from the rest of the bus the data on the bus can be directly assigned to this isolated group or device and the rest of the bus.
This is what the segment mode of the analyzer provides. The bus is split into two segments of any size and the common data on the bus can be unequivocally assigned to a sender in the correct segment. By variations of the two segments the faulty device can be encircled and detected.
More entries concerning the segment mode:
How does the segment mode work